1. Technical Field
This invention relates to emergency fire fighting and rescue systems for high-rise buildings, and particularly to systems that incorporate an outside elevator using an exterior track on an outside wall of the building.
2. Background Art
The development of hydraulically operated high lift ladders for fire engines has reduced the importance of external fire escapes for relatively low multistory buildings, but the maximum reach of such ladders is only about twelve stories. As the result of several major fires in high-rise hotel and office buildings, there has been increased attention directed to the problem of evacuating people from the upper floors of very tall buildings in an emergency when interior elevators and stairways cannot be used.
Examples of external elevator systems for emergency evacuation and fire fighting are disclosed in U.S. Pat. Nos. 4,018,306 of LYONS; 4,569,418 of NOVARINI; and 4,664,226 of CENTANNE. These systems use cable hoists or rack and pinion drives to raise and lower cars or gondolas on a vertical rail or rails that are mounted on the exterior face of a building.
One of the objections to installing such a system on many buildings is that the permanent presence of vertical rails on the face of the building would mar the appearance and architectural integrity of the design. In addition, on many buildings there is no external structure to which to secure the rails. This is particularly true of glass sheathed and other curtain wall buildings in which the entire exterior surface consists of relatively lightweight panels secured by clips to the building frame.
Penetrations through these this building skins for permanent rail supports not only would be unsightly but also would be sites for potential leaks.